Diagnostic Considerations of Intermetatarsal Bursitis: A Systematic Review

Abstract

Intermetatarsal bursitis (IMB) is an inflammation of the intermetatarsal bursas. The condition causes forefoot pain with symptoms similar to those of Morton’s neuroma (MN). Some studies suggest that IMB is a contributing factor to the development of MN, while others describe the condition as a differential diagnosis. Among patients with rheumatic diseases, IMB is frequent, but the scope is yet to be understood. The aim of this paper was to investigate the diagnostic considerations of IMB and its role in metatarsalgia by a systematic review approach. We identified studies about IMB by searching the electronic databases Pubmed, Embase, Cochrane Library, and Web of Science in September 2022. Of 1362 titles, 28 met the inclusion criteria. They were subdivided according to topic: anatomical studies (n = 3), studies of patients with metatarsalgia (n = 10), and studies of patients with rheumatic diseases (n = 15). We conclude that IMB should be considered a cause of pain in patients with metatarsalgia and patients with rheumatic diseases. For patients presenting with spreading toes/V-sign, IMB should be a diagnostic consideration. Future diagnostic studies about MN should take care to apply a protocol that is able to differ IMB from MN, to achieve a better understanding of their respective role in forefoot pain.

Current and future advances in practice: mechanical foot pain

“…Within the forefoot, inter-metatarsal bursae are located between the MTP joints, dorsal to the deep transverse inter-metatarsal ligament [ 40 ]. Inter-metatarsal bursitis occurs owing to excessive friction or pressure from the surrounding tissues [ 41 , 42 ]. Likewise, adventitial plantar bursitis develops in the soft tissues of the forefoot beneath the MTP joints owing to excessive shearing and pressure from the bony structures of the foot with the weight-bearing surface [ 42 , 43 ].…”

Écartement des orteils causé par une bursite intermétatarsienne chez une personne atteinte de polyarthrite rhumatoïde

“…La bursite intermétatarsienne est une inflammation des bourses situées entre les têtes métatarsiennes du côté dorsal du ligament métatarsien transverse profond (annexe 1, accessible en anglais au www.cmaj.ca/lookup/doi/10.1503/cmaj.231253/tab-related-content ) 1 . Le diagnostic différentiel de la métatarsalgie avec écartement des orteils comprend le névrome de Morton, la bursite intermétatarsienne et les nodules rhumatoïdes, ainsi que la déformation du pied d’origine traumatique ou dégénérative 2 .…”

“…Il y a une corrélation notable entre la bursite intermétatarsienne et la présence d’anticorps anti-CCP et de facteur rhumatoïde chez les personnes atteintes de polyarthrite rhumatoïde 3 . On rapporte aussi que la bursite intermétatarsienne est un signe diagnostique utile de la polyarthrite rhumatoïde, avec une sensibilité (69 %) et une spécificité (70 %) raisonnables 1 . La présence simultanée d’une métatarsalgie et d’un élargissement de l’espace interdigital entre 2 orteils adjacents chez des personnes chez qui l’on soupçonne une forme d’arthrite inflammatoire peut être un signe de bursite intermétatarsienne, ce qui devrait évoquer la polyarthrite rhumatoïde.…”

Separating toes due to intermetatarsal bursitis in rheumatoid arthritis

“…Intermetatarsal bursitis refers to the inflammation of the bursas found between the metatarsal heads located on the dorsal side of the deep transverse metatarsal ligament (Appendix 1, available at www.cmaj.ca/lookup/doi/10.1503/cmaj.231253/tab-related-content ). 1 The differential diagnosis of patients with metatarsalgia and toes spreading includes Morton neuroma, IMB and rheumatoid nodules, in addition to traumatic and degenerative foot deformity. 2 Ultrasonography of IMB shows a characteristic hypoechoic, Doppler-positive structure between the metatarsal heads, as seen in our patient.…”

“…The presence of IMB is significantly associated with anti-CCP and rheumatoid factor positivity among patients with rheumatoid arthritis; 3 IMB is also reported as a useful diagnostic finding for rheumatoid arthritis with reasonable sensitivity (69%) and specificity (70%). 1 Metatarsalgia with widened interdigital space separating 2 adjacent toes in patients with suspected inflammatory arthritides, can indicate the presence of IMB, suggestive of rheumatoid arthritis.…”